Lisa at Over the Big Moon blog, made some Professor Snape potions. Awesome right? So authentic and they totally belong in Professor Snape's potion closet. She even has a free printable so you can make your own potions (Here). If not this year, I'm totally going to make some of these next year.
As well she made these sweet looking dementors to hang in her living room. I hope she has lots of chocolate on hand...and someone who can cast a good patronus. Want to make some yourself, she even has a tutorial.